BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE 
35 
NEW DEVICE FOR DISTRIBUTING CONCENTRATED SPRAYS FROM AIRPLANES 
In previous seasons insecticides to control gypsy moths from air- 
craft have been applied only in dust form. Satisfactory adherence of 
the dust to foliage could not be secured. This season lead arsenate 
and cryolite in concentrated spray form were distributed from a spe- 
cially devised spinner-disk apparatus attached to a biplane. The 
mortality of gypsy moths approximated 100 percent in all areas treated 
with lead arsenate, and reasonably satisfactory control was obtained 
in the areas treated with cryolite. The aerial method of application 
of insecticides for gypsy moth control is now considered to have 
passed the experimental stage; its effectiveness and economy of oper- 
ation have been demonstrated. 
COOPERATION WITH OTHER AGENCIES 
As a result of the cooperation of State agencies, Bureau research 
units, and the public, surveys were conducted on a larger acreage than 
was covered in any previous year ; the adhesiveness, and consequently 
the effectiveness, of the insecticides was increased; and other project 
activities were performed with a considerably reduced personnel. 
Cooperative control on an experimental basis was conducted with 
the Dominion of Canada against the spruce budworm and with New 
York State against a destructive species of sawfly, to determine the 
effectiveness of distributing new insecticide formulas w T ith the spin- 
ner-disk type of apparatus attached to aircraft. Preliminary obser- 
vations indicate that very effective control was obtained. 
INCREASE IN INTENSITY OF INFESTATION 
A decided increase in intensity of gypsy moth infestation has been 
noted in a small area in Pennsylvania and in the north-central portion 
of Massachusetts. From observations made at the close of the year, 
it is estimated that more than 200,000 acres of forest land were severely 
damaged by heavy to complete defoliation, compared with 35.000 
acres during the previous year. During the last 3 years gypsy moth 
populations, except in the Cape Cod area of Massachusetts, have been 
at the lowest ebb since 1924. 
BROWN-TAIL MOTH CONTROLLED BY STATES 
Brown-tail moths are present only in the four northern New Eng- 
land States, and all work on control during the year was conducted 
by the affected States. Very little defoliation or heavy feeding was 
rioted, except in a few areas along the coast near the Maine-New 
Hampshire State line. 
CERTIFICATION OF PRODUCTS UNDER THE GYPSY AND BROWN- 
TAIL MOTHS QUARANTINE 
Gypsy moth infestation resulted in little defoliation in the summer 
of 1943, according to reports of district inspectors stationed through- 
out New England. This was not the situation in June 1944, however. 
Enormous damage to woodlands by gypsy moth larvae was reported 
in sections of Massachusetts, Maine, and New Hampshire, particularly 
in the Cape Cod and Northampton-Belchertown areas of Massachu- 
